The invention relates to a stop assembly for a sheet pile edge in a sheet-processing machine and, more particularly, to such a stop assembly that is constructed as a rotatably mounted, adjustable-format roller.
For the purpose of separating sheets from the top of a sheet pile, suction elements are used which are assisted by blower or blast devices, strippers and a sensing element that generates a signal for tracking the pile. The pile, which is offset laterally a predefined target course, is seated centrally in relation to the sheet-processing machine, in particular, a printing machine. In order to achieve as constant a target course as possible, as well as sheet leading edges running in parallel with the front lays and a uniform sheet arrival time, the pile or at least the upper sheets of the pile should be aligned as accurately as possible in the circumferential and lateral directions before being separated. Such pre-stacking or pre-pile formation activities are generally performed manually. In this regard, a stop that is adjustable to the format serves to guide the pile in the upper region thereof.
A stop of this type is disclosed, for example, in German Patent 667 527. The stop includes one or more rollers which, in accordance with the format, is settable against a lateral edge of the sheet pile.
The rollers described in this German patent are not mounted so that the height thereof is adjustable. Exact positioning is therefore not assured.
It is accordingly an object of the invention to provide a stop for a sheet pile edge by which the pile is aligned, at least in the upper region of the pile.
With the foregoing and other objects in view, there is provided, in accordance with the invention, an assembly of at least one stop for a sheet pile edge in a sheet-processing machine, the stop being constructed as a rotatably mounted, adjustable-format roller, comprising a vertically pivotable link whereon the roller is disposed so as to be adjustable in height.
In accordance with another feature of the invention, the assembly includes another stop constructed as a roller for acting with the first-mentioned roller upon a trailing edge of the sheet pile.
In accordance with a further feature of the invention, the assembly includes two additional stops constructed as rollers, respectively, for acting upon lateral edges of the sheet pile.
In accordance with an added feature of the invention, the assembly includes further stops constructed as rollers, the one stop and the further stops being arranged so that they are displaceable and lockable along trailing and lateral edges of the sheet pile.
In accordance with an additional feature of the invention, the assembly includes an additional stop assigned to the one roller.
In accordance with yet another feature of the invention, the additional stop is pivotally mounted.
In accordance with yet a further feature of the invention, the assembly includes at least two additional stops assigned to the one and the further rollers.
In accordance with a concomitant feature of the invention, the additional stops are pivotally mounted.
It is an advantage of the invention that the stop according to the invention is aligned with the upper sheets in the circumferential direction. Due to this measure, it is also possible to process sheet piles which are not aligned absolutely exactly in the circumferential direction, i.e., in the sheet transport direction.
A further advantage resides in the arrangement of the stops according to the invention in the upper side or lateral region of the sheet pile; due to this measure, the sheet pile is brought laterally into the provided position.
The stops according to the invention are constructed as rotatably mounted rollers, both in the rear or trailing edge region and in the lateral edge region.
Mounting the rotatable roller so that it is pivotable permits the roller to execute a virtually vertical deflection movement. By this measure, it is possible to bring up a pile board so close to the separating or singling elements that even the last sheets of a sheet pile can be processed. In a further advantageous configuration of the invention, each alignment roller has an auxiliary or additional stop assigned thereto which, when the roller makes contact with the pile board, performs the alignment function.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a stop for a sheet stack edge, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, wherein: